The Class Osteostraci ("Bony Shields") was a group of bony-armored jawless fish, termed "ostracoderms", that lived in what is now North America, Europe and Russia from the Middle Silurian to Late Devonian.
Anatomically speaking, the osteostracans, especially the Devonian species, were among the most advanced of all known agnathans. This is due to the development of paired fins, and their complicated cranial anatomy. However, the osteostracans were more related to other agnathans than to jawed vertebrates as their inner ears are formed by two pairs of semicircular canals, similar to those of living lampreys, as opposed to the three pairs found in the inner ears of jawed vertebrates.
Researchers from University of Alberta Report Details of New Studies and Findings in the Area of Vertebrate Paleontology
Dec 21, 2012; By a News Reporter-Staff News Editor at Science Letter -- Research findings on Vertebrate Paleontology are discussed in a new...